4/7/17: Yep, that's Lethe, changing her hair up again. The cut's pretty much what she had a few months before she found the Fictional World, minus short bangs and the dye job. She still has just a tiny tint of red on the longest parts of her 'do. I'm not completely satisfied with the tone of her "dirty blond" hair, so there may be slight changes ahead on her exact shade. I also tried out a new marker color on Kuuki's hair, but messed up a little.
The general idea here is that she's cooped herself up mostly in her room, trying to figure everything out on her own. I imagine any attempts to get her out previously were politely turned down. Oh, and Fianne has access to emergency keys for all the rooms, it's just more fun to use an poleaxe instead.